Liquid Crystal Displays (LCDs) have been widely applied in various products or components having display functions, such as smartphones, tablet computer, televisions, displays, notebook computers, cameras, video recorders, digital photo frames, navigators and the like, due to their advantages of low power consumption, light weight, thinness, free of electromagnetic radiation and free of pollution.
In a conventional LCD, a pixel array may include gate scan lines and data lines that are interlaced with each other. In order to achieve progressive scanning of a pixel array, a gate driver circuit is typically used for providing the gate scan lines of the pixel array with scanning signals.
Conventionally, a gate driver circuit typically employs a Gate Driver on Array (GOA) design where a Thin Film Transistor (TFT) gate switching circuit is integrated onto an array substrate of a display panel, so as to constitute a scanning driver for the display panel. Such gate driver circuit integrated onto the array substrate utilizing the GOA technique is also referred to as a GOA circuit or a shift register circuit.
However, in the conventional shift register unit, when a load on an output port is increased, its output capability degrades. In order to improve the output capability with the conventional structure, the width of its transistor channel has to be increased significantly, which will occupy a large design space.